Scouts are wary of hailed improvements and once-in-a-lifetime performances at on-campus pro days, and you should be too. NFLDraftScout.com publisher Frank Cooney breaks down how teams dissect pro day numbers.

We already know who the big names in college football are heading into the 2013 season. Players like Johnny Manziel, Jadeveon Clowney, A.J. McCarron, Marqise Lee and Aaron Murray will be the focus of much of the preseason hype. And rightfully so, as they've proven themselves on the field time and time again.

Now that the deadline for underclassmen entering the NFL Draft has passed, it's time to check in on the programs hit the hardest by early departure and, yes, it's the SEC that took the brunt of early exits.